The molecular structures of metallic alloys and ceramic materials differ substantially from each other. In the metallic bond, the electrons orbit the atomic nuclei disorderly and with comparatively low bonding force. Ions, for example in the body environment, separate constantly from this “loose” structure; a variety of chemical reactions are possible.
In ceramic molecules, the electrons in the ceramic bond follow precisely predefined paths, the so-called directed electron orbitals. Their bonding force is very high; the molecules are extremely stable. Therefore, no formation of ions takes place and chemical reactions are virtually impossible.